Liquefied petroleum gas (LPG) sensing using spray deposited Cu2ZnSnS4 thin film

In the present work, Cu2ZnSnS4 (CZTS) thin films deposited using the spray pyrolysis method are employed for liquefied petroleum gas (LPG) sensing. The structural, morphological, wettability and compositional properties of CZTS thin films are studied using X-ray diffraction (XRD), Fourier transform Raman (FT-Raman) spectroscopy, field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), contact angle measurement and energy dispersive X-ray spectroscopy (EDS) techniques. The XRD and FT-Raman spectroscopy studies show formation of single phase CZTS with kesterite structure. FE-SEM analysis reveals nanospherical architecture with pin-hole and crake free surface. Electrical measurement indicates that CZTS thin film exhibits p-type semiconducting behavior. The CZTS thin film shows highest selectivity toward LPG as compared to other gases (i.e. 62 % for LPG, 16 % for N-2, 13 % for CO2 and 10 % for H-2) with response and recovery time periods of 40 and 43 s, respectively at a concentration of 1040 ppm. (C) 2015 Elsevier B.V. All rights reserved.